CN202872324U - Protection circuit and switching power supply with same - Google Patents
Protection circuit and switching power supply with same Download PDFInfo
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- CN202872324U CN202872324U CN 201220591059 CN201220591059U CN202872324U CN 202872324 U CN202872324 U CN 202872324U CN 201220591059 CN201220591059 CN 201220591059 CN 201220591059 U CN201220591059 U CN 201220591059U CN 202872324 U CN202872324 U CN 202872324U
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Abstract
The embodiment of the utility model discloses a protection circuit and a switching power supply with the same. The protection circuit comprises a current detection unit and an over-protection unit, wherein in the over-protection unit, the positive pole of a first diode is connected with the current detection unit, and the negative pole of the first diode is connected with the negative pole of a second diode; the positive pole of the second diode is connected with the first end of a first thermistor; the second end of the first thermistor is connected to a voltage output end; the first end of a second resistor is connected with the first end of the first thermistor, and the second end of the second resistor is earthed; and the positive pole of a voltage-regulating tube is connected with the negative pole of the first diode, and the negative pole of the voltage-regulating tube is connected with the base electrode of a triode. According to the over-protection unit circuit, the voltage of a pin at the enabling end of a control chip is lowered through reducing the voltage of the collector end of the triode, thereby prompting the control chip to turn off, and protecting components in the protection circuit from being burned to be damaged by large currents or high temperatures.
Description
Technical field
The utility model relates to technical field of electricity, relates in particular a kind of protective circuit and the Switching Power Supply with this protective circuit.
Background technology
In circuit application, usually need with the components and parts in the control chip protective circuit, when preventing the excessive or excess Temperature of electric current in the circuit, cause the damage of components and parts.Most of control chip has the current detecting pin, can realize the function of overcurrent, overheat protector.
For example; pulse-width modulation (Pulse Width Modulation, PWM) control chip can be applied in the DC-DC circuit, when electric current is higher than certain value greater than certain value or temperature; pwm chip can turn-off automatically, and the components and parts in the protective circuit are not burnt.
But in the prior art, the overcurrent of control chip, overheat protector function and unsound.At first, it can only in the current protection scope that it can be controlled, realize overcurrent protection.When electric current surpasses its protection range, then only limit the power protection, can make the lower voltage of protected circuit part, the electric current in the protected circuit is reduced, in this case, can cause the damage of components and parts in the circuit.In addition; the overheat protector of control chip is uncontrollable; only when the temperature of control chip is higher than its specified protection temperature value; just can automatically shut down, realize the overheat protector function, temperature is very high in circuit; but when not reaching the specified protection temperature value of control chip; control chip can not automatically shut down, and in this case, also can cause the damage of components and parts in the circuit.
The utility model content
In view of this; the utility model provides a kind of protective circuit and has the Switching Power Supply of this protective circuit; solve control chip and when electric current is too high, only limit the power protection; when causing that temperature does not reach the specified protection temperature of control chip in the excessive problem of easily burning components and parts of electric current and the circuit; so that control chip can not be realized overheat protector, and the problem of damage components and parts.
For achieving the above object, the utility model provides following technical scheme:
A kind of protective circuit comprises current detecting unit and overprotection unit;
Described overprotection unit comprises: the first diode, the second diode, the first thermistor, the second resistance, voltage-stabiliser tube and triode; Wherein:
The anode of described the first diode links to each other with described current detecting unit, and negative electrode links to each other with the negative electrode of described the second diode;
The anode of described the second diode links to each other with the first end of described the first thermistor;
The second end of described the first thermistor is connected to voltage output end, and the first end of described the second resistance links to each other with the first end of described the first thermistor, the second end ground connection;
The positive pole of described voltage-stabiliser tube links to each other with the negative electrode of described the first diode, and negative pole links to each other with the base stage of described triode;
The grounded emitter of described triode, collector electrode are used for linking to each other with the Enable Pin pin of control chip.
Preferably, described overprotection unit also comprises the 3rd resistance, and the first end of described the 3rd resistance links to each other with the second end of described thermistor, and the second end is connected to voltage output end.
Preferably, described current detecting unit comprises current transformer, the 3rd diode, filter capacitor, the 4th resistance, the 5th resistance and the 6th resistance, wherein:
The first end of described current transformer is used for the input of electric current, and the second end links to each other with the first end of described the 4th resistance, and the 3rd end is used for linking to each other with the current detecting pin of control chip, and the 4th end is used for the output of electric current;
The second end of described the 4th resistance links to each other with the 3rd end of described current transformer;
The anode of described the 3rd diode links to each other with the second end of described current transformer, and negative electrode links to each other with the first end of described filter capacitor;
The second end of described filter capacitor links to each other with the 3rd end of described current transformer;
The first end of described the 5th resistance links to each other with the negative electrode of described the 3rd diode, the second end ground connection;
The first end of described the 6th resistance links to each other with the 3rd end of described current transformer, the second end ground connection.
A kind of Switching Power Supply comprises control chip and protective circuit described above.
Preferably, described control chip is pulse-width modulation (PWM) control chip.
Via above-mentioned technical scheme as can be known; compared with prior art; the utility model openly provides a kind of protective circuit and has had the Switching Power Supply of this protective circuit; in described protective circuit; when the current value in the electric circuit inspection unit surpasses the current range that control chip can protect; flow through the electric current energy of voltage-stabiliser tube so that the triode conducting; thereby drag down the voltage of control chip Enable Pin pin; so that control chip turn-offs; realize overcurrent protection function; solved in the prior art; control chip can only be realized overcurrent protection in certain current protection scope; when surpassing the current value of protection range, only limit the power protection, thereby cause large electric current to damage the problem of components and parts in the circuit.
In addition; in described protective circuit; the second end of the first thermistor is connected to voltage output end; the resistance of the first thermistor can constantly reduce along with the rising of temperature; because the total voltage of the first thermistor and the second resistance is constant; the voltage at the second resistance two ends can constantly raise along with the reduction of the first thermistor resistance; through the voltage behind the second diode so that the corresponding reverse-conduction current of voltage-stabiliser tube is increasing; when voltage reaches certain value; the electric current of flowing through can impel the triode conducting; so that the lower voltage of transistor collector end; and then drag down the voltage of control chip Enable Pin pin; so that control chip turn-offs, realize the overheat protector function.In described protective circuit; the temperature value that can bear according to side circuit; the size of the magnitude of voltage of the second end by changing the first thermistor or select the first suitable thermistor R1 and the second resistance R 2 according to the temperature value that size and the protected circuit of magnitude of voltage can bear; realization is to the overheat protector of different temperatures; solved in the prior art; when the temperature in the circuit did not reach the specified protection temperature of control chip, control chip can not be realized the overheat protector function and cause circuit temperature too high and damage the problems of components and parts in the circuit.
Description of drawings
In order to be illustrated more clearly in the utility model embodiment or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art, apparently, accompanying drawing in the following describes only is embodiment of the present utility model, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to the accompanying drawing that provides other accompanying drawing.
Fig. 1 is the circuit structure diagram of a kind of embodiment of a kind of protective circuit of the present utility model;
Fig. 2 is the circuit structure diagram of another embodiment of a kind of protective circuit of the present utility model.
Embodiment
Below in conjunction with the accompanying drawing among the utility model embodiment, the technical scheme among the utility model embodiment is clearly and completely described, obviously, described embodiment only is the utility model part embodiment, rather than whole embodiment.Based on the embodiment in the utility model, those of ordinary skills are not making the every other embodiment that obtains under the creative work prerequisite, all belong to the scope of the utility model protection.
Referring to Fig. 1, the circuit structure diagram of an embodiment of a kind of protective circuit of the present utility model is shown.
In conjunction with Fig. 1, described protective circuit comprises current detecting unit 101 and overprotection unit 102.
Wherein, described overprotection unit 102 comprises: the first diode D1, the second diode D2, the first thermistor R1, the second resistance R 2, voltage-stabiliser tube Z1 and triode Q1; Wherein:
The anode of described the first diode D1 links to each other with described current detecting unit 101, and negative electrode links to each other with the negative electrode of described the second diode D2;
The anode of described the second diode D2 links to each other with the first end of described the first thermistor R1;
The second end of described the first thermistor R1 is connected to voltage output end;
The first end of described the second resistance R 2 links to each other with the first end of described the first thermistor R1, the second end ground connection;
The positive pole of described voltage-stabiliser tube Z1 links to each other with the negative electrode of described the first diode D1, and negative pole links to each other with the base stage of described triode Q1;
The grounded emitter of described triode Q1, collector electrode are used for linking to each other with the Enable Pin pin of control chip, and namely the IC_EN end is used for connecting the Enable Pin pin of control chip.
Wherein, the second end of the first thermistor is connected to voltage output end; described voltage output end provides certain magnitude of voltage V0 for the second end of described the first thermistor R1; concrete; the second end of described the first thermistor R1 can directly link to each other with external power supply, perhaps can link to each other with the voltage source in the protected circuit.
In actual applications, the size of described magnitude of voltage V0 is concrete the restriction not, the size of the Temperature Setting magnitude of voltage V0 that can bear according to the protected circuit of reality;
Wherein, if the second end of described the first thermistor R1 is directly connected to the voltage source in the protected circuit; the temperature value that the magnitude of voltage that then can provide according to described voltage source and protected circuit can bear is selected the first suitable thermistor R1 and the second resistance R 2; so that the temperature in protected circuit is when being higher than the temperature value that it can bear, described protective circuit can realize the overheat protector function.
Wherein, in order to guarantee when the temperature of described protective circuit changes; the change in resistance amount of described the first thermistor R1 can change the voltage swing at described the second resistance R 2 two ends significantly; described protective circuit can also comprise the 3rd resistance; described the 3rd resistance first end links to each other with the second end of described the first thermistor R1; concrete, the second end of described the 3rd resistance is connected to voltage output end.
In described protective circuit; increase along with electric current in the current detecting unit; voltage through the first diode can make reverse-conduction current corresponding to voltage-stabiliser tube increasing; until make the complete reverse-conducting of voltage-stabiliser tube; when the voltage of voltage-stabiliser tube positive terminal reaches certain value; the electric current that flows through voltage-stabiliser tube can impel the triode conducting; increase along with transistor base and the pressure drop of collector electrode two ends; the terminal voltage of collector electrode can decrease; thereby drag down the voltage of control chip Enable Pin pin; impel control chip to turn-off, realize excess current protective function, the components and parts in the protective circuit are not damaged by large electric current.
Described protective circuit can be when electric current be excessive; by dragging down the voltage of control chip Enable Pin pin; realize overcurrent protection; solved in the prior art; control chip can only be realized overcurrent protection in certain current protection scope; when surpassing the current value of protection range, only limit the power protection, thereby cause large electric current to damage the problem of components and parts in the circuit.
When described protective circuit work; the resistance of the first thermistor also can constantly reduce along with the rising of temperature; thereby so that the voltage at the second resistance two ends constantly improves; also can be so that the corresponding reverse-conduction current of voltage-stabiliser tube be increasing through the voltage behind the second diode; when voltage reaches certain value; the electric current of flowing through can impel the triode conducting; increase along with transistor base and the pressure drop of collector electrode two ends; the voltage of collector terminal also decreases; and then drag down the voltage of the Enable Pin pin of control chip; so that control chip turn-offs, realize the overheat protector function.
In described protective circuit, the temperature value that can bear according to protected circuit is set the size of the magnitude of voltage V0 of the voltage output end that links to each other with described the first thermistor the second end; When described magnitude of voltage V0 is fixed value; the temperature value that also can bear according to size and the protected circuit of magnitude of voltage V0 is selected the first suitable thermistor R1 and the second resistance R 2; so that the temperature in protected circuit is when being higher than the temperature value that it can bear; described protective circuit can realize the overheat protector function; solved in the prior art; when the temperature in the circuit did not reach the specified protection temperature of control chip, control chip can not be realized the overheat protector function and cause circuit temperature too high and damage the problems of components and parts in the circuit.
In the protective circuit of this enforcement; along with the increase of the voltage-stabiliser tube electric current of flowing through, so that thereupon the reducing of the voltage of triode end collector terminal, and then drag down the voltage of control chip Enable Pin pin; impel control chip to turn-off, the components and parts in the protective circuit are not bad by large electric current or high temperature scaling loss.
In described protective circuit, described current detecting unit has different implementations, as a kind of embodiment, referring to Fig. 2, the circuit structure diagram of the another embodiment of a kind of protective circuit of the utility model is shown.
In conjunction with Fig. 2, described current detecting unit 101 comprises current transformer L1, the 3rd diode D3, filter capacitor C1, the 4th resistance R 4, the 5th resistance R 5 and the 6th resistance R 6; Wherein:
The first end 1 of described current transformer L1 is used for the input of electric current, the second end 2 links to each other with the first end of described the 4th resistance R 4, the 3rd end 3 is used for linking to each other with the current detecting pin of control chip, be that IC CS end is used for linking to each other with the current detecting pin of control chip, the 4th end 4 is used for the output of electric current;
The second end of described the 4th resistance R 4 links to each other with the 3rd end of described current transformer L1;
The anode of described the 3rd diode D3 links to each other with the second end of described current transformer L1, and negative electrode links to each other with the first end of described filter capacitor C1;
The second end of described filter capacitor C1 links to each other with the 3rd end of described current transformer L1;
The first end of described the 5th resistance R 5 links to each other with the negative electrode of described the 3rd diode D3, the second end ground connection;
The first end of described the 6th resistance R 6 links to each other with the 3rd end of described current transformer L1, the second end ground connection.
Wherein, the first end 1 of described current transformer and the 4th end 4 can be connected to be needed in the protected circuit; first end 1 is used for the input of electric current; the 4th end 4 is used for the output of electric current; current transformer L1 is reduced the electric current of input in certain proportion at secondary; then through after the 3rd diode D3 rectification, the filter capacitor C1 filtering; the 5th resistance R 5 of flowing through and the 6th resistance R 6; wherein; the voltage at R6 two ends is fed to the current detecting pin of control chip as current detection signal, be used for control chip and control opening and turn-offing of himself.
Wherein, described current transformer L1 can change original large electric current in the circuit into current transformer secondary very little electric current in certain proportion, has reduced the power loss of current detecting part.
In described protective circuit; the voltage at the 5th resistance R 5 two ends is the detection signal of overcurrent or short circuit; when the electric current that passes through described current transformer L1 is very large; the voltage at the 5th resistance R 5 two ends also can be increasing; voltage through the first diode D1 can make reverse-conduction current corresponding to voltage-stabiliser tube Z1 increasing; until make the complete reverse-conducting of voltage-stabiliser tube; when the voltage of voltage-stabiliser tube positive terminal reaches certain value; the electric current that flows through voltage-stabiliser tube can impel triode Q1 conducting; increase along with transistor base and the pressure drop of collector electrode two ends; the terminal voltage of collector electrode can decrease; thereby drag down the voltage of the Enable Pin pin of control chip; impel control chip to turn-off, realize excess current protective function, the components and parts in the protective circuit are not damaged by large electric current.When overcurrent or short circuit were removed, described protective circuit was recovered normal operating conditions.
And when not being very large through the electric current of described current transformer L1, the voltage at the 5th resistance R 5 two ends can be less, so that triode Q1 conducting, then the overprotection unit can not play overcurrent protection function through the undertension of voltage-stabiliser tube.But in certain current range, self has overcurrent protection function control chip.
In described protective circuit; the total voltage of described the first thermistor and described the second resistance is V0; when the temperature in the circuit raises; the resistance of the first thermistor can decrease; the voltage that bear at described the first thermistor two ends also can reduce; the voltage that is described the second resistance two ends can raise; also can be so that the corresponding reverse-conduction current of voltage-stabiliser tube be increasing through the voltage behind the second diode; when the voltage of voltage-stabiliser tube reaches certain value; the electric current of flowing through can impel the triode conducting; increase along with transistor base and the pressure drop of collector electrode two ends; the voltage of collector terminal also decreases; and then drag down the Enable Pin voltage of control chip, so that control chip turn-offs, realize the overheat protector function.
When the temperature value that can bear when protected circuit temperature does not reach the specified protection temperature of control chip, also can be by setting the magnitude of voltage V0 of the voltage output end that links to each other with described the first thermistor the second end, so that described protective circuit realization overheat protector; Perhaps select the second resistance R 2 of different resistances according to the size of magnitude of voltage V0 and the temperature value that protected circuit can bear, so that the temperature in protected circuit is when being higher than the temperature value that it can bear, described protective circuit can realize the overheat protector function.
Therefore, the difference of the temperature value that can bear according to protected circuit by the magnitude of voltage V0 of setting voltage output, or is selected the second resistance R 2 of different resistances, realizes the overheat protector function to different temperatures in the protected circuit, and is simple and convenient.
For the ease of understanding, with PWM(Pulse Width Modulation, pulse-width modulation) control chip is that example describes.In pwm chip being applied to certain protected circuit, establish current range that its pwm chip can protect at 17.5 amperes ~ 33 amperes; If its specified protection temperature is 150 ℃.
In DC-DC DCDC circuit, when the electric current by pwm chip current detecting pin less than 17.5 ampere-hours, the pwm chip normal operation; When the electric current that passes through pwm chip current detecting pin is between 17.5 amperes and 33 amperes, pwm chip can be realized overcurrent protection function, can turn-off voluntarily, intermittently protective circuit, when current value was reduced to below 17.5 amperes, pwm chip recovered normal operating conditions; And ought pass through the electric current of pwm chip current detecting pin greater than 33 ampere-hours; the pwm chip cisco unity malfunction; at this moment; pwm chip is only limit the power protection; namely can only be so that the output voltage reduction; can not make the current reduction that passes through, if without the overprotection unit, then can burn the components and parts in the circuit.
In addition, when pwm chip was worked, when only having temperature when control chip to be higher than 150 ℃ of specified protection temperature, pwm chip could turn-off voluntarily, realizes overheat protector.And when the temperature of control chip is lower than 150 ℃, can not realize the overheat protector function.
And in protective circuit of the present utility model, when the electric current that flows through described current transformer L1 when not being very large, for example between 17.5 amperes and 33 amperes, the electric current that flows through voltage-stabiliser tube Z1 can not impel triode Q1 conducting, at this moment namely, the overprotection unit does not play overcurrent protection function, but owing to the protection range at pwm chip, can realize overcurrent protection function by pwm chip; When the electric current that flows through described current transformer L1 surpasses certain value; for example 33 amperes; in described overprotection unit; the electric current that flows through voltage-stabiliser tube Z1 can impel triode Q1 conducting; the voltage that is the transistor collector end can reduce along with the rising of electric current; thereby drag down the voltage of pwm chip Enable Pin, so that pwm chip turn-offs, realize overcurrent protection function.
In described protective circuit; because the resistance of described the first thermistor can constantly reduce along with the rising of temperature; so that the voltage at described the first thermistor two ends also constantly reduces; the voltage at described the second resistance two ends can increase; can be by setting the magnitude of voltage V0 of described the first thermistor the second end; perhaps select the second resistance R 2 of different resistances according to the size of magnitude of voltage V0 and the temperature value that protected circuit can bear; so that the temperature in protected circuit is during less than 150 ℃; described protective circuit also can be by dragging down the Enable Pin voltage of control chip; so that control chip turn-offs, realize the overheat protector function.
In the present embodiment, by with being used in conjunction with of current detecting unit and overprotection unit and control chip, remedy defective and the deficiency of original chip, perfected the Global Macros function of circuit; And overcurrent, overheat protector design in same circuit, realize this two defencive functions with the simplest minimum components and parts, save device cost and space.
Described protective circuit can be applicable in the Switching Power Supply, and a kind of Switching Power Supply comprises control chip and as the described protective circuit of above-mentioned embodiment.
Wherein, described control chip can be pwm chip.
In actual applications, protective circuit can be applied in the DC-DC circuit, or interchange turns in the DC circuit, is used for preventing that the components and parts of circuit from being damaged by large electric current or high temperature.
It is as an embodiment, described protective circuit can be applied to DC-DC BUCK(decompression transformation) in the switch power converter of circuit framework, after system powers on, under the effect of control chip, filter capacitor, metal-oxide-semiconductor, inductance etc. are passed through in the input of voltage between 22V ~ 32V, being transformed into voltage is that 13.5V, rated current are the output of 13.5A, and the electric current of its over-current protection point is 17.5A, and the electric current of maximum over-current protection point is 33A;
When the load current of the described switch power converter of flowing through was between over-current protection point 17.5A and maximum over-current protection point 33A, control chip can be realized overcurrent protection by the shutoff of control self; When load current during greater than 33A, described protective circuit then can by dragging down the voltage of described control chip Enable Pin pin, realize overcurrent protection;
Simultaneously; according to the practical application of switch power converter and the performance parameter of used components and parts, 110 ℃ of the temperature values that mensuration can bear are by selecting the first suitable thermistor R1 and the second resistance R 2; so that described protective circuit when temperature surpasses 110 ℃, realizes the overheat protector function.
Each embodiment adopts the mode of going forward one by one to describe in this specification, and what each embodiment stressed is and the difference of other embodiment that identical similar part is mutually referring to getting final product between each embodiment.For the disclosed device of embodiment, because it is corresponding with the disclosed method of embodiment, so description is fairly simple, relevant part partly illustrates referring to method and gets final product.
To the above-mentioned explanation of the disclosed embodiments, make this area professional and technical personnel can realize or use the utility model.Multiple modification to these embodiment will be apparent concerning those skilled in the art, and General Principle as defined herein can be in the situation that do not break away from spirit or scope of the present utility model, in other embodiments realization.Therefore, the utility model will can not be restricted to these embodiment shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.
Claims (5)
1. a protective circuit is characterized in that, comprises current detecting unit and overprotection unit;
Described overprotection unit comprises: the first diode, the second diode, the first thermistor, the second resistance, voltage-stabiliser tube and triode; Wherein:
The anode of described the first diode links to each other with described current detecting unit, and negative electrode links to each other with the negative electrode of described the second diode;
The anode of described the second diode links to each other with the first end of described the first thermistor;
The second end of described the first thermistor is connected to voltage output end, and the first end of described the second resistance links to each other with the first end of described the first thermistor, the second end ground connection;
The positive pole of described voltage-stabiliser tube links to each other with the negative electrode of described the first diode, and negative pole links to each other with the base stage of described triode;
The grounded emitter of described triode, collector electrode are used for linking to each other with the Enable Pin pin of control chip.
2. circuit according to claim 1 is characterized in that, described overprotection unit also comprises the 3rd resistance, and the first end of described the 3rd resistance links to each other with the second end of described thermistor, and the second end is connected to voltage output end.
3. circuit according to claim 1 is characterized in that, described current detecting unit comprises current transformer, the 3rd diode, filter capacitor, the 4th resistance, the 5th resistance and the 6th resistance, wherein:
The first end of described current transformer is used for the input of electric current, and the second end links to each other with the first end of described the 4th resistance, and the 3rd end is used for linking to each other with the current detecting pin of control chip, and the 4th end is used for the output of electric current;
The second end of described the 4th resistance links to each other with the 3rd end of described current transformer;
The anode of described the 3rd diode links to each other with the second end of described current transformer, and negative electrode links to each other with the first end of described filter capacitor;
The second end of described filter capacitor links to each other with the 3rd end of described current transformer;
The first end of described the 5th resistance links to each other with the negative electrode of described the 3rd diode, the second end ground connection;
The first end of described the 6th resistance links to each other with the 3rd end of described current transformer, the second end ground connection.
4. a Switching Power Supply is characterized in that, comprises control chip and such as the described circuit of any one in the claim 1 ~ 3.
5. Switching Power Supply according to claim 4 is characterized in that, described control chip is pulse-width modulation (PWM) control chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220591059 CN202872324U (en) | 2012-11-09 | 2012-11-09 | Protection circuit and switching power supply with same |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 201220591059 CN202872324U (en) | 2012-11-09 | 2012-11-09 | Protection circuit and switching power supply with same |
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| CN202872324U true CN202872324U (en) | 2013-04-10 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103683402A (en) * | 2013-12-02 | 2014-03-26 | 淮南市长安机电设备有限公司 | Coal mine equipment power source with protection circuit |
| CN109274067A (en) * | 2018-10-18 | 2019-01-25 | 郑州云海信息技术有限公司 | A kind of thermal-shutdown circuit and server system of secondary power supply plate |
| CN109441865A (en) * | 2018-10-18 | 2019-03-08 | 郑州云海信息技术有限公司 | A kind of thermal-shutdown circuit and server system of fan board |
| CN109830936A (en) * | 2019-02-26 | 2019-05-31 | 深圳乐桥电子有限公司 | A kind of current foldback circuit solving PTC breakdown |
| CN113765057A (en) * | 2021-08-10 | 2021-12-07 | 茂硕电源科技股份有限公司 | Overvoltage protection circuit, device and equipment |
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2012
- 2012-11-09 CN CN 201220591059 patent/CN202872324U/en not_active Expired - Lifetime
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103683402A (en) * | 2013-12-02 | 2014-03-26 | 淮南市长安机电设备有限公司 | Coal mine equipment power source with protection circuit |
| CN109274067A (en) * | 2018-10-18 | 2019-01-25 | 郑州云海信息技术有限公司 | A kind of thermal-shutdown circuit and server system of secondary power supply plate |
| CN109441865A (en) * | 2018-10-18 | 2019-03-08 | 郑州云海信息技术有限公司 | A kind of thermal-shutdown circuit and server system of fan board |
| CN109830936A (en) * | 2019-02-26 | 2019-05-31 | 深圳乐桥电子有限公司 | A kind of current foldback circuit solving PTC breakdown |
| CN113765057A (en) * | 2021-08-10 | 2021-12-07 | 茂硕电源科技股份有限公司 | Overvoltage protection circuit, device and equipment |
| CN113765057B (en) * | 2021-08-10 | 2024-01-23 | 茂硕电源科技股份有限公司 | Overvoltage protection circuit, device and equipment |
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| C14 | Grant of patent or utility model | ||
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| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: 4 / F, building 1, No.14 Jiuxianqiao Road, Chaoyang District, Beijing 100020 Patentee after: Beijing Jingwei Hirain Technologies Co.,Inc. Address before: 100101 Beijing city Chaoyang District Anxiang Beili 11 B block 8 layer Patentee before: Beijing Jingwei HiRain Technologies Co.,Ltd. |
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| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20130410 |